Joint osteotomy system and method

ABSTRACT

A system includes a first spacer sized and configured to be received within a resected bone space of a first bone and a second spacer sized and configured to be coupled to a second bone. The first spacer and the second spacer each include a body extending between a bone contacting surface and a coupling surface. At least one shim is positioned between the first and second spacers. The shim includes a body extending between a first coupling surface and a second coupling surface. The first spacer, the second spacer, and the at least one shim position the first and second bones in a predetermined alignment. An adjustable guide including a guide adapter and a guide body is configured to couple to the first spacer and is adjustable on a first axis.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.16/669,809, filed Oct. 31, 2019, which is a continuation of co-pendingU.S. patent application Ser. No. 16/668,639, filed Oct. 30, 2019, whichis a continuation of International Patent Application No.PCT/US2017/044419, filed on Jul. 28, 2017, the entireties of which areincorporated by reference herein.

BACKGROUND

The ankle is a joint that acts much like a hinge. The joint is formed bythe union of three bones. The ankle bone is the talus. The top of thetalus fits inside a socket that is formed by the lower end of the tibiaand the fibula, the small bone of the lower leg. Arthritis, bonedegeneration, and/or injury can cause ankle joint deteriorationresulting in pain, reduced range of motion, and decreased quality oflife. In many cases, physicians are recommending ankle replacementsurgery with an implant as an option.

A primary ankle replacement surgery can include replacement of portionsof one or more of the bones of the ankle with one or more implants. Theprimary ankle replacement surgery can correct misalignments,deformities, and other issues of the ankle joint. In some cases, arevision surgery is necessary to correct additional deformities,misalignments, or other issues of the ankle joint not corrected during aprimary ankle replacement surgery and/or that develop after the primaryankle replacement surgery.

SUMMARY

In various embodiments, a system includes a first spacer sized andconfigured to be received within a joint space of a first bone. Thefirst spacer defines a body extending between a first surface and asecond surface. The system further includes an adjustable guide includesa guide adapter and a guide body. The guide adapter is configured tocouple the adjustable guide to the first spacer. The guide body isadjustable along a first axis with respect to the guide adapter.

In various embodiments, a system includes a first spacer sized andconfigured to be received within a joint space of a first bone. Thefirst spacer defines a body extending between a first surface and asecond surface. The system further includes at least one shim comprisinga body extending between an upper surface and a lower surface. The uppersurface is configured to couple the at least one shim to the secondsurface of the first spacer. The system also includes an adjustableguide comprising a guide adapter configured to be coupled the firstspacer and a guide body. The guide body comprises a first leg and asecond leg extending from the guide body and spaced apart to define aslot sized and configured to receive a coupling element extending fromthe guide adapter. The guide body is adjustable along a first axis withrespect to the guide adapter.

In various embodiments, a method includes coupling a first spacer to ajoint space of a first bone. The first spacer defines a body extendingbetween a first surface and a second surface. The first surface ispositioned in contact with the first bone. A second spacer is coupled toa second bone. The second spacer defines a body extending between afirst surface and a second surface. The second surface of the firstspacer is configured to abut the second surface of the second spacer toposition the first bone and the second bone in a predeterminedalignment. An adjustable guide is coupled to one of the first spacer orthe second spacer.

In various embodiments, a system includes a first spacer sized andconfigured to be received within a joint space of a first bone, a secondspacer sized and configured to be coupled to a second bone, and at leastone shim comprising a body extending between an upper surface and alower surface. The first spacer and the second spacer each include abody extending between a first surface and a second surface. the uppersurface of the at least one shim is configured to couple the at leastone shim to the second surface of the first spacer and the lower surfaceis configured to couple the at least one shim to the second surface ofthe second spacer. The first spacer, the second spacer, and the at leastone shim are configured to position the first bone and the second bonein a predetermined alignment.

In various embodiments, a system includes a first spacer sized andconfigured to be received within a resected bone space of a first bone,a second spacer sized and configured to be coupled to a second bone, andat least one shim comprising a body extending between an upper surfaceand a lower surface. The first spacer and the second spacer each includea body extending between a first surface and a second surface. The firstsurface of the first spacer is configured to couple the first spacer toa lock detail of an implant coupled to the first bone. The upper surfaceof the at least one shim is configured to couple the at least one shimto the second surface of the first spacer and the lower surface isconfigured to couple the at least one shim to the second surface of thesecond spacer. The first spacer, the second spacer, and the at least oneshim are configured to position the first bone and the second bone in apredetermined alignment.

In various embodiments, a method includes coupling a first spacer to ajoint space of a first bone. The first spacer defines a body extendingbetween a first surface and a second surface. The bone contactingsurface is positioned in contact with the resected bone space. A secondspacer is coupled to a second bone. The second spacer defines a bodyextending between a first surface and a second surface. An upper surfaceof a first shim is coupled to the second surface of the first spacer anda lower surface of the first shim is coupled to the second surface ofthe second spacer. The first spacer and the second spacer position thefirst bone and the second bone in a predetermined alignment. The firstshim has a predetermined thickness configured to correct laxity betweenthe first bone and the second bone.

In various embodiments, a system includes a first spacer sized andconfigured to be received within a joint space of a first bone and asecond spacer sized and configured to be coupled to a second bone. Thefirst spacer includes a body extending between a first surface and asecond surface. The second surface defines an adjustment channel. Thesecond spacer includes a body extending between a first surface and asecond surface and an adjustment body extending from the second surface.The adjustment body is sized and configured to be inserted into theadjustment channel in a telescoping arrangement. The first spacer andthe second spacer are configured to position the first bone and thesecond bone in a predetermined alignment.

In various embodiments, a method includes coupling a first spacer to ajoint space of a first bone. The first spacer includes a body extendingbetween a first surface and a second surface. The second surface definesan adjustment channel extending into the body. A second spacer iscoupled to a second bone. The second spacer includes a body extendingbetween a first surface and a second surface and an adjustment bodyextending from the second surface. The adjustment body is sized andconfigured to be inserted into the adjustment channel in a telescopingarrangement. The first spacer and the second spacer are configured toposition the first bone and the second bone in a predeterminedalignment. A spacing between the first spacer and the second spacer isadjusted by sliding the adjustment body within the adjustment channel.The spacing between the first spacer and the second spacer is configuredto correct for laxity between the first bone and the second bone.

In various embodiments, a system includes a monolithic spacer having abody extending between a first surface and a second surface and anadjustable guide. The first surface is configured to abut a joint spaceof a first bone and the second surface includes a patient-specifictopography matching a second bone. The adjustable guide includes a guideadapter configured to be coupled the monolithic spacer and a guide bodydefining a resection slot. The guide body comprises a first leg and asecond leg extending from the guide body and spaced apart to define aslot sized and configured to receive a coupling element extending fromthe guide adapter.

In various embodiments, a system includes a body sized and configured tobe receiving within a joint space and defining a tool path extendingfrom a first side of the body to a second side of the body. The toolpath is sized and configured to receive a surgical tool therethrough. Afirst bone engaging structure extends from the body in a firstdirection. The first bone engaging structure includes a first surfacethat is complementary to a surface topography of the bone. A drill guideis sized and configured to be received within tool path defined by thebody. The drill guide defines an aperture sized and configured toreceive the surgical tool therethrough. At least one shim is configuredto be coupled to a bottom surface of the body. The shim includes acoupling element extending from an upper surface and the body defines afirst complementary recess sized and configured to receive the couplingelement therein.

In various embodiments, a system includes a first spacer sized andconfigured to be received within a joint space of a first bone and afirst shim. The first spacer defines a body extending between a firstsurface and a second surface. The first shim includes a body extendingbetween an upper surface and a lower surface. The upper surface isconfigured to couple the first shim to the second surface of the firstspacer and the lower surface is configured to abut a second bone toposition the first bone and the second bone in a predeterminedalignment.

In various embodiments, a method includes positioning a first spacerwithin a joint space of a first bone and coupling a first shim to asurface of the first spacer. The first bone and a second bone arepositioned in a predetermined alignment by abutting the first shim withthe second bone.

BRIEF DESCRIPTION OF THE FIGURES

The features and advantages of the present invention will be more fullydisclosed in, or rendered obvious by the following detailed descriptionof the preferred embodiments, which are to be considered together withthe accompanying drawings wherein like numbers refer to like parts andfurther wherein:

FIG. 1 illustrates the bones of a human foot and ankle;

FIGS. 2A and 2B are schematic representations of a scanned image of ahuman foot and ankle joint;

FIG. 3 illustrates a bone preparation instrument coupled to a first boneby a conversion instrument, in accordance with some embodiments;

FIG. 4 illustrates a front side plan view of the bone preparationinstrument of FIG. 3, in accordance with some embodiments;

FIG. 5 illustrates a side view of the bone preparation instrument ofFIG. 3, in accordance with some embodiments.

FIG. 6 illustrates a spacer assembly positioned between a first bone anda second bone of a joint, in accordance with some embodiments;

FIG. 7 illustrates a side view of the spacer assembly of FIG. 6, inaccordance with some embodiments;

FIG. 8 illustrates a front view of the spacer assembly of FIG. 6, inaccordance with some embodiments;

FIG. 9 illustrates an exploded view of the spacer assembly of FIG. 6, inaccordance with some embodiments;

FIG. 10 illustrates an isometric view of a first spacer positionedwithin a resected bone space of a first bone, in accordance with someembodiments;

FIG. 11 illustrates a front view of the first spacer of FIG. 10, inaccordance with some embodiments;

FIG. 12 illustrates a bottom isometric view of the first spacer of FIG.10, in accordance with some embodiments;

FIG. 13 illustrates another embodiment of a first spacer configured tobe positioned within a resected bone space of a first bone, inaccordance with some embodiments;

FIG. 14 illustrates an isometric view of a second spacer configured toabut a second bone, in accordance with some embodiments;

FIG. 15 illustrates a bottom isometric view of the second spacer of FIG.14, in accordance with some embodiments;

FIG. 16 illustrates an isometric view of a shim, in accordance with someembodiments;

FIG. 17 illustrates a bottom view of the shim of FIG. 16, in accordancewith some embodiments;

FIG. 18 illustrates an isometric view of an adjustable guide, inaccordance with some embodiments;

FIG. 19 illustrates an exploded view of the adjustable guide of FIG. 18,in accordance with some embodiments;

FIG. 20 illustrates a side view of a guide adapter of the resectionguide of FIG. 18, in accordance with some embodiments;

FIG. 21 illustrates a top view of the guide adapter of FIG. 20, inaccordance with some embodiments;

FIG. 22 illustrates an isometric view of a guide body of the adjustableguide of FIG. 18, in accordance with some embodiments;

FIG. 23 illustrates a front view of the resection guide of FIG. 22, inaccordance with some embodiments;

FIG. 24 illustrates a rear isometric view of the resection guide of FIG.22, in accordance with some embodiments;

FIG. 25 illustrates an isometric view of a locking knob of theadjustable guide of FIG. 18, in accordance with some embodiments;

FIG. 26 illustrates a top view of the locking knob of FIG. 25, inaccordance with some embodiments;

FIG. 27 illustrates the spacer assembly of FIG. 6 having one or moreguide elements inserted through an adjustable guide assembly, inaccordance with some embodiments.

FIG. 28 illustrates the guide body of FIG. 22 coupled to a first guideelement and a second guide element, in accordance with some embodiments.

FIG. 29 illustrates a spacer assembly including a first spacerconfigured to be coupled to an implant installed in a first bone, inaccordance with some embodiments

FIG. 30 illustrates the spacer assembly of FIG. 29 having an adjustableguide coupled thereto, in accordance with some embodiments.

FIG. 31 illustrates a spacer assembly including a monolithic spacer, inaccordance with some embodiments;

FIG. 32 illustrates an isometric view of the monolithic spacer of FIG.31, in accordance with some embodiments;

FIG. 33 illustrates a rear view of the monolithic spacer of FIG. 32, inaccordance with some embodiments;

FIG. 34 illustrates a spacer assembly including a monolithic spacer anda cutting guide coupled thereto, in accordance with some embodiments;

FIG. 35 illustrates a spacer assembly including a first spacer and asecond spacer coupled in a telescoping arrangement, in accordance withsome embodiments;

FIG. 36 illustrates an isometric view of a first spacer and a secondspacer coupled in a telescoping arrangement, in accordance with someembodiments;

FIG. 37 illustrates a first spacer of the spacer assembly of FIG. 36, inaccordance with some embodiments;

FIG. 38 illustrates a second spacer of the spacer assembly of FIG. 36,in accordance with some embodiments;

FIG. 39 illustrates an isometric view of a spacer assembly including afirst spacer and one or more shims configured to abut a second bone of ajoint, in accordance with some embodiments;

FIG. 40 illustrates an isometric view of a spacer assembly including afirst spacer and a fixed angle shim configured to abut a second bone ofa joint, in accordance with some embodiments;

FIG. 41 illustrates the fixed angle shim of FIG. 40, in accordance withsome embodiments;

FIG. 42 illustrates a drill guide mount configured to be coupled to atleast one shim, in accordance with some embodiments; and

FIG. 43 illustrates the drill guide mount of FIG. 42 coupled to a firstbone and a first shim configured to be coupled to the drill guide mount,in accordance with some embodiments.

DETAILED DESCRIPTION

This description of the exemplary embodiments is intended to be read inconnection with the accompanying drawings, which are to be consideredpart of the entire written description. In the description, relativeterms such as “lower,” “upper,” “horizontal,” “vertical,”, “above,”“below,” “up,” “down,” “top,” “bottom,” “proximal,” “distal,”“superior,” “inferior,” “medial,” and “lateral” as well as derivativethereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should beconstrued to refer to the orientation as then described or as shown inthe drawing under discussion. These relative terms are for convenienceof description and do not require that the apparatus be constructed oroperated in a particular orientation. Terms concerning attachments,coupling and the like, such as “connected,” refer to a relationshipwherein structures are secured or attached to one another eitherdirectly or indirectly through intervening structures, as well as bothmovable or rigid attachments or relationships, unless expresslydescribed otherwise. Like elements have been given like numericaldesignations to facilitate an understanding of the present subjectmatter.

As used herein, the term “substantially” denotes elements having arecited relationship (e.g., parallel, perpendicular, aligned, etc.)within acceptable manufacturing tolerances. For example, as used herein,the term “substantially parallel” is used to denote elements that areparallel or that vary from a parallel arrangement within an acceptablemargin of error, such as +/−5°, although it will be recognized thatgreater and/or lesser deviations can exist based on manufacturingprocesses and/or other manufacturing requirements.

The disclosed systems and methods may advantageously utilize custommanufactured surgical instruments, guides, and/or fixtures that arebased upon a patient's anatomy to maximize the accuracy of the guidesand/or surgical instruments during a surgical procedure. These custominstruments, guides, and/or fixtures may be created by imaging apatient's anatomy with a computer tomography (“CT”) scanner, a magneticresonance imaging (“MRI”) machine, or like medical imaging technologyprior to surgery and utilizing these images to create patient-specificinstruments, guides, and/or fixtures. This is generally termed as apreoperative assessment or plan and may be used in conjunction withintra-operative tools to accurately implement such a plan. Exemplarypreoperative assessments or plans may allow a surgeon to specify thesize, position, and/or orientation of a patient's anatomical componentsand/or subsequent implant components within the joint or bone at issuebased upon preoperative CT or MRI images. Of course, final componentsize and position may be determined intra-operatively through directvisualization of the implants or various sizing instrumentation by thesurgeon with or without the aid of fluoroscopy.

The disclosed systems and methods can be applied to a revision surgeryfor primary replacement of ankle joint 12. Examples of primary ankletechniques using patient-specific surgical jigs and fixtures aredescribed in U.S. Patent Appl. Pub. No. 2015/0257899, published Sep. 17,2015, entitled “Ankle Replacement System and Method” and U.S. Pat. No.8,808,303, issued on Aug. 19, 2014 and entitled “Orthopedic SurgicalGuide,” each of which is incorporated by reference herein in itsentirety. Although the following description of the custompatient-specific instruments are described with respect to a foot 10 andankle 12 (FIG. 1), one of ordinary skill in the art will understand thatthe systems and methods may be utilized in connection with other jointsincluding, but not limited to, knees, hips, shoulders, and the like. Asshown in FIG. 1, a typical human foot 10 includes an ankle joint 12formed between a talus 14, which is disposed on a calcaneus 20, a tibia16, a fibula 18, and a navicular 22.

Upon completion of a primary replacement surgery, one or morearticulation surfaces of ankle joint 12 are replaced with one or moreimplants. For example, in some embodiments, tibial implant and/or atalar implant replace articulation surfaces of a talus 12 and/or a tibia14, respectively. A revision procedure is applied to a joint that haspreviously been subject to a replacement procedure. The revisionprocedure modifies the joint replacement through making additionalresections, replacing existing implants with alternative implants,and/or adding additional or removing implants at the joint. For example,in some embodiments, the systems and methods disclosed herein can beused for an ankle revision procedure in which the ankle joint haspreviously been subject to a replacement procedure.

During a primary and/or a revision surgery, a CT or MRI scanned image orseries of images may be taken of a patient's ankle 12 (or other joint)and then converted from, e.g., a DICOM image format, to a solid computermodel of the ankle including the calcaneus, talus, tibia, navicular, andfibula to determine implant alignment, type, and sizing usingspecialized modeling methods that are often embodied in computersoftware. Computer generated models (e.g., CAD models) that are derivedfrom the data of the CT or MRI scan image will often include precise andaccurate information regarding the surface contours surrounding thestructures that have been imaged, e.g., the surface topography of thebones or contour of connected tissue (e.g., fascia, cartilage, etc.)that have been imaged. Imaging and generation of patient-specificimplants is further described in U.S. Pat. No. 5,768,134, issued on Jun.16, 1998, entitled “Method for Making a Perfected Medical Model on theBasis of Digital Image Information of a Part of the Body,” which isincorporated herein by reference in its entirety. In some embodiments,the CT and/or MRI scan image includes foreign bodies, such as one ormore implants previously installed in the joint 12 during a primaryreplacement surgery, as described in greater detail in InternationalPatent Application No. PCT/US15/20414, which published as WO2016/148675, which is incorporated herein in its entirety. It will beunderstood that by surface topography it is meant the location, shape,size and distribution of surface features such as concavities andprominences or the like.

In some embodiments, after establishing a primary ankle replacement, arevision procedure can be performed re-using instrumentation from theprimary replacement procedure and/or using additional instrumentation.For example, in some embodiments, a revision procedure can include theuse of a conversion instrument 200. The conversion instrument 200 isconfigured to couple a cutting guide to one of the first bone 14 and/orthe second bone 16 to allow one or more revision resections to beformed. The revision resections are configured to further modify thefirst bone 14 and/or the second bone 16 to receive alternative and/oradditional revision implants.

As illustrated in FIGS. 3-5, in some embodiments, a guide 250 and aconversion instrument 200 can be coupled to a first bone 14 by slidingthe guide 250 and/or the conversion instrument 200 over one or more pinsinserted into the first bone 14. As best seen in FIG. 4, conversioninstrument 200 includes an elongate body 202 extending from a region forfixation (shown at the proximal end 204 in the illustrated embodiment)to a region for attaching other bone preparation instruments (shown atthe distal end 206 in the illustrated embodiment). Conversion instrument200 includes a first and second oblong sections 208, 210 that extendtransversely with respect to the longitudinal direction of instrument200. Each oblong section 208, 210 defines a respective plurality ofinterconnected holes 212, 214.

The distal end 206 of instrument 200 includes a dovetail joint 216defining a cavity 218 between rails 220 at the distal end 206 ofinstrument 200. Cavity 218 is sized and configured to receive a lockingwedge 222 as best seen in FIG. 5. A through-hole 224 extends from afirst side 226 to a second side 228 of the distal end 206 of instrument200 and is sized and configured to receive a locking bolt 230 therein.Locking bolt 230 is configured to a press locking wedge against adovetail member 252 of a guide 250, such as a cut guide, a drill guide,and/or coronal sizing and drill guide. Holes 258 are defined by thedistal end 206 of instrument 200 on either side of dovetail joint 216.Holes 258 are sized and configured to receive pins 210 therein.

The conversion instrument 200 can be secured to a guide 250 by havingdovetail extension 252 of guide 250 be received within dovetail joint216. A hex driver is used to tighten locking bolt 230 within hole 224.The rotation of locking bolt 230 causes the engagement end of lockingbolt, which can be threaded or have another engagement feature disposedthereon, engage a corresponding structure disposed within distal end ofinstrument 200 and axially move such that shoulders of bolt 230 contactangled surfaces of a locking wedge. The axial movement of bolt 230forces the bottom surface of the locking wedge against dovetailextension, which is frictionally locked by rails 220. Additionalexamples of positioning and use of the conversion instrument 200 aredisclosed in U.S. Pat. Appl. Pub. 2015/0257899, published on Sep. 17,2015, and entitled “Ankle Replacement System and Method,” which waspreviously incorporated herein in its entirety.

As discussed above, during a revision surgery, one or more additionaland/or alternative revision cuts can be formed in a bone, such as firstbone 14 and/or second bone 16. In some embodiments, a revision cuttingguide can be positioned with reference to a preoperatively planneddeformity correction based on anatomic references and/or surgeonpreferences. The joint 12 can be positioned to match the pre-operativelyplanned deformity correction using a spacer assembly. The spacerassembly positions the first bone 14 and/or the second bone 16 in thepreoperatively planned deformity correction and further guides theplacement of a revision cutting guide, as discussed in greater detailbelow.

FIG. 6 illustrates a spacer assembly 300 positioned between a first bone14 and a second bone 16 of a joint 12 and an adjustable guide 600coupled thereto, in accordance with some embodiments. Spacer assembly300 includes a first spacer 400 and a second spacer 500. First spacer400 and second spacer 500 are configured to position the first bone 14and the second bone 16 in a corrected alignment. In some embodiments,the corrected alignment of joint 12 corresponds to a preoperativelyplanned deformity correction that is planned based on anatomicreferences and/or surgeon preferences. Spacers 400, 500 set one or moredegrees of freedom of joint 12. For example, in various embodiments, thespacers 400, 500 can correct one or more of a varus/valgus orientation,a flexion/extension orientation, an inversion/eversion orientation, ananterior/posterior position, a medial/lateral position, and/or aproximal/distal position between the first bone 14 and the second bone16 intraoperatively. The first spacer 400, the second spacer 500, and/orthe adjustable guide 600 may be manufactured from a resilient polymermaterial of the type that is suitable for use in connection with stereolithography, selected laser sintering, 3D printing, or the likemanufacturing equipment, e.g., a polyamide powder repaid prototypematerial is suitable for use in connection with the selective lasersintering.

As illustrated in FIG. 9, first spacer 400 includes a first (or bonecontacting) surface 404 configured to abut first bone 16 and secondspacer 500 includes a first (or bone contacting) surface 504 configuredto abut second bone 16. Each of first spacer 400 and second spacer 500further include respective second (or coupling) surfaces 406, 506configured to be positioned in an abutting relationship. When spacers400, 500 are positioned against respective first and second bones 14,16, respective coupling surfaces 406, 506 are abutting and positionfirst and second bones 14, 16 to surface-match the anatomy of the joint12 in a corrected alignment. For example, in various embodiments, thespacers 400, 500 position the first bone and a second bone in one ormore of a pre-operatively determined varus/valgus orientation,flexion/extension orientation, inversion/eversion orientation,anterior/posterior position, medial/lateral position, and/orproximal/distal position. Although embodiments are discussed having afirst spacer 400 and/or a second spacer 500 coupled to a bone, it willbe appreciated that the first spacer 400 and/or the second spacer 500can be coupled to an implant installed in a bone, such as an implantinstalled during a prior replacement surgery and/or installedconcurrently during a current replacement and/or revision surgery.

As best shown in FIG. 7, in some embodiments, an adjustable guide 600 isconfigured to couple to one or both of first spacer 400 and/or secondspacer 500. Adjustable guide 600 is adjustable in one or more directionswith respect to spacers 400, 500 and/or the joint 12 to set a resectiondepth and/or position for first bone 14 and/or second bone 16. Forexample, in some embodiments, adjustable guide 600 is adjustable in aproximal/distal direction, a superior/inferior direction, and/or anyother suitable direction with respect to spacers 400, 500. Theadjustable guide is configured to locate a revision cut in second bone16. Although embodiments are discussed herein including an adjustableguide 600 configured to locate a revision cut in second bone 16, it willbe appreciated that adjustable guide 600 can include guide elementscorresponding to additional and/or alternative cuts and/or revisions infirst bone 14 and/or second bone 16.

FIGS. 10-12 illustrate a first spacer 400 a configured to abut firstbone 14, in accordance with some embodiments. In some embodiments, firstspacer 400 a is configured to interface with existing bone, cartilage,and/or other soft tissue of first bone 14. For example, in someembodiments, first spacer 400 a is a tibial spacer configured to abut atibia. In other embodiments, first spacer 400 a is configured to abut apre-existing implant coupled to the first bone 14. The pre-existingimplant can include an implant inserted during a previous anklereplacement surgery and/or inserted during a current ankle replacementsurgery.

Spacer 400 a includes a body 402 having a thickness extending between abone contacting surface 404 and an opposing coupling surface 406. Body402 further extends longitudinally between a proximal surface 408 a anda distal surface 408 b, as best seen in FIG. 10, and has a widthextending between a first side surface 410 a and a second side surface410 b as best seen in FIG. 11. Body 402 is sized and configured forinsertion into a resected portion of first bone 14. Bone contactingsurface 404 defines a patient-specific profile complimentary to asurface of the first bone 14. For example, bone contacting surface 404can be configured to interface with existing bony anatomy of first bone14 and/or cartilage or other soft tissue coupled to first bone 14.

As best seen in FIGS. 10 and 12, body 402 defines one or more firstfixation holes 416 a, 416 b extending therethrough. First fixation holes416 a, 416 b extend from one of first or second side surfaces 410 a, 410b to the other of first and second side surfaces 410 a, 410 b. Thefixation holes 416 a, 416 b are angled with respect to first and secondside surfaces 410 a, 410 b such a first side of each of the fixationholes 416 a, 416 b is positioned proximally of a second side. In someembodiments, fixation holes 416 a, 416 b extend through body 402 alongintersecting hole axis, although it will be appreciated that thefixation holes 416 a, 416 b can extend through the body 402 alongnon-intersecting hole axis in some embodiments.

In some embodiments, a bone engaging structure 412 extends from aproximal surface 408 a of body 402 in a superior direction above bonecontacting surface 404. Bone engaging structure 412 has a lengthextending between a bone contacting surface 414 a and an opposingsurface 414 b, a thickness extending between an upper surface 420 a anda lower surface 420 b, and a width extending between a first sidesurface 426 a and a second side surface 426 b. In some embodiments, bonecontacting surface 414 a includes a patient-specific profile configuredto surface-match a portion of first bone 14 and/or soft-tissue coupledto first bone 14. Bone engaging structure 412 is configured to abut asurface of first bone 14 and maintain the first spacer 400 a in a fixedanterior/posterior position with respect to first bone 14. In someembodiments, the portion of the first bone 14 that is surface-matched bybone engaging structure 412 is the anterior surface of a tibia, althoughone of ordinary skill in the art will understand that bone engagingstructure can be configured to surface match other bones and surfaces.

Referring now to FIG. 11, bone engaging structure 412 defines a slot 430extending from opposing surface 414 b at least partially into block 412.In some embodiments, slot 430 extends from opposing surface 414 b tobone contacting surface 414 a. Slot 430 is sized and configured toreceive a portion of a resection guide 600 therein, such as a flatcoupling element 612 described in greater detail with respect to FIGS.18-21. In some embodiments, bone engaging structure 412 defines one ormore second fixation holes 428 a-428 b extending from opposing surface414 b to bone contacting surface 414 a. Second fixation holes 428 a-428b are each sized and configured to receive a fixation elementtherethrough. The fixation elements can include any suitable fixationelement, such as a k-wire, screw, pin, and/or any other suitablefixation element. In some embodiments, the fixation elements areconfigured to maintain first spacer 400 in a fixed position with respectto first bone 14. In some embodiments, first fixation holes 416 a-416 band/or second fixation holes 428 a-428 b include a positioncorresponding to one or more fixation elements previously coupled to thefirst bone 14 by one or more additional surgical elements.

In some embodiments, coupling surface 406 of spacer 400 a is configuredto abut and/or couple to spacer 500 as best seen in FIG. 6. Couplingsurface 406 includes a recess 422 extending from a proximal edge ofcoupling surface 406 proximally into the body 402. Recess 422 is sizedand configured to receive a complementary coupling feature of secondspacer 500, such as a mating protrusion 510, discussed in greater detailwith respect to FIGS. 14-15. Recess 422 couples first spacer 400 a tosecond spacer 500 in a predetermined arrangement. In some embodiments,recess 422 is a U-shaped recess, although it will be appreciated thatrecess 422 can have any shape complementary to the shape of matingprotrusion 510 of second spacer 500.

In some embodiments, coupling surface 406 defines a dovetail joint 440.Dovetail joint 440 has a similar construction to the dovetail joint 216described above with respect to the conversion instrument 200. A cavity442 is defined in a coupling surface 406 between rails 444 as best seenin FIG. 11. Cavity 442 is sized and configured to receive acorresponding dovetail extension 712 extending from a shim 700, asdiscussed in greater detail with respect to FIGS. 16-17. Althoughembodiments are discussed herein including a dovetail joint 440, it willbe appreciated that the coupling surface 406 can define any suitablestructure or cavity sized and configured to couple to an extension 712defined by the shim 700. In some embodiments, the dovetail joint 440 isomitted.

With reference to FIG. 13, in some embodiments, a first spacer 400includes a bone engaging extension 418 extending from an upper surface420 a of bone engaging structure 412. Bone engaging extension 418extends above upper surface 420 a of the bone engaging structure 412.Bone engaging extension 418 includes a body 450 extending between a bonecontacting surface 452 a and an opposing surface 452 b. In someembodiments, bone contacting surface 452 b is surface-matched to aportion of first bone 14. Bone engaging extension 418 defines at leastalignment hole 424 extending therethrough. Alignment hole 424 isconfigured to provide a visual indication during fluoroscopy and/orother imaging procedures to ensure proper alignment of the first spacer400 prior to insertion of one or more fixation elements.

FIGS. 14-15 illustrates another example of a second spacer 500 aconfigured to abut second bone 16, in accordance with some embodiments.The second spacer 500 a is similar to the second spacer 500 discussedabove in conjunction with FIGS. 6-9, and similar description is notrepeated herein. Second spacer 500 a is configured to interface withexisting bone, cartilage, and/or other soft tissue of second bone 16.For example, in some embodiments, second spacer 500 a is a talar spacerconfigured to abut a talus. In other embodiments, second spacer 500 a isconfigured to abut a pre-existing implant coupled to second bone 16. Thepre-existing implant can include an implant inserted during a previousankle replacement surgery and/or inserted during a current anklereplacement surgery.

In some embodiments, second spacer 500 a includes a body 502 having athickness extending between a bone contacting surface 504 and a couplingsurface 506. The body 502 further extends longitudinally between aproximal surface 508 a and a distal surface 508 b and has a widthextending between a first side surface 510 a and a second side surface510 b. Body 502 is sized and configured to abut a portion of second bone16 and/or soft tissue coupled to second bone 16, such as a resectedand/or non-resected superior surface of second bone 16. In someembodiments, bone contacting surface 504 defines a patient-specificprofile surface-matched to second bone 14.

Coupling surface 506 is positioned in an opposing relationship withcoupling surface 406 of first spacer 400 a when first and second spacers400 a, 500 a are positioned within joint 12. In some embodiments, eachof the coupling surfaces 406, 506 define a planar surface. Couplingsurface 506 can have a greater, lesser, and/or equal surface area ascoupling surface 406. Although embodiments are discussed hereinincluding planar coupling surfaces 406, 506, it will be appreciated thatcoupling surfaces 406, 506 can have any suitable matching surfacetopography configured to position first bone 14 and second bone 16 inone or more of a pre-operatively determined varus/valgus orientation,flexion/extension orientation, inversion/eversion orientation,anterior/posterior position, medial/lateral position, and/orproximal/distal position.

In some embodiments, a mating element 512 extends from coupling surface506. Mating element 512 is sized and configured to couple second spacer500 a to one or more superiorly positioned elements, such as firstspacer 400 a. In some embodiments, mating element 512 includes acylindrical protrusion sized and configured to be received withinchannel 420 formed in coupling surface 406. The coupling between matingelement 512 and channel 420 provides constraint of one or more degreesof freedom (such as medial/lateral, proximal/distal etc.) of joint 12while allowing for adjustment of one or more other degrees of freedom(such as internal/external rotational flexibility, anterior/posteriortranslation, etc.) of joint 12. Although embodiments are discussedherein including a cylindrical protrusion, it will be appreciated thatmating element 512 can include any suitable cross-section configured forinsertion into channel 420 and can extend any suitable distance abovecoupling surface 506.

In some embodiments, second spacer 500 a defines one or more fixationholes 514 a-514 b each being respectively sized and configured toreceive a fixation element therein. Fixation holes 514 a-514 b extendfrom a first surface, such as coupling surface 506 and/or proximalsurface 508 a, to a second surface, such as bone contact surface 504and/or distal surface 508 b. Each of the fixation elements can includeany suitable fixation element, such as a k-wire, a screw, and a pin, tolist only a few possibilities. Second spacer 500 a is maintained in afixed position with respect to second bone 16 by inserting one or morefixation elements through one or more of fixation holes 514 a-514 b. Insome embodiments, one or more of fixation holes 514 a-514 b include aposition corresponding to a fixation element previously coupled tosecond bone 16 by one or more additional surgical instruments and/orguides.

In some embodiments, a bone engaging structure 520 extends in aninferior direction from the body 502. The bone engaging structure has alength extending between a bone contacting surface 522 a and an opposingsurface 522 b, a thickness extending between an upper surface 524 a anda lower surface 524 b, and a width extending between a first sidesurface 526 a and a second side surface 526 b. In some embodiments, bonecontacting surface 522 a and/or lower surface 524 b include apatient-specific profile configured to surface-match a portion of firstbone 16 and/or soft-tissue coupled to first bone 16. Bone engagingstructure 520 is configured to abut a surface of first bone 16 andmaintain second spacer 500 a in a fixed anterior/posterior position withrespect to second bone 16.

In some embodiments, laxity can exist between first bone 14 and secondbone 16 after installation of the first spacer 400 and/or the secondspacer 500. Laxity in joint 12 may not be fully known pre-operativelyand/or may change intra-operatively, for example, due to ligamentrelease, tendon release, tendon transfer, osteotomy, etc. In someembodiments, one or more shims 700 can be inserted between respectivespacers 400, 500 to distract first bone 14 from second bone 16. FIGS.16-17 illustrate a shim 700 configured to be positioned between firstspacer 400 and second spacer 500 to correct laxity in joint 12, inaccordance with some embodiments. Shim 700 may be manufactured from aresilient polymer material of the type that is suitable for use inconnection with stereo lithography, selected laser sintering, or thelike manufacturing equipment, e.g., a polyamide powder repaid prototypematerial is suitable for use in connection with the selective lasersintering.

Shim 700 includes a body 702 extending between an upper surface 704 anda lower surface 706. Body 702 has a predetermined thickness extendingfrom the upper surface 704 to the lower surface 706, such as, forexample, a thickness in the range of 1 mm-6 mm, such as 1 mm, 2 mm, 2.5mm, 3 mm, 3.5 mm, 4 mm, 5 mm, and/or any other suitable thickness. Body702 extends longitudinally between a proximal side 708 a and a distalside 708 b and has a width extending between a first side 710 a and asecond side 110 b. In some embodiments, body 702 can have a generallyrectangular shape, although it will be appreciated that body 702 canhave any suitable regular and/or irregular shape configured to bereceived within a joint space between a first bone and a second bone. Insome embodiments, body 702 is sized and configured to correspond to oneor more of the coupling surfaces 406, 506 of respective first and secondspacers 400, 500.

In some embodiments, upper surface 704 includes a dovetail extension 712configured to couple shim 700 to first spacer 400 and/or a shimpositioned in contact with the upper surface 704. The dovetail extension712 includes a projection 714 sized and configured to be inserted withincavity 442 formed in first spacer 400. The dovetail extension 712 ispositioned at a proximal edge of the upper surface 704, although it willbe appreciated that dovetail extension 712 can extend from any suitablelocation of upper surface 704 such that dovetail extension 712 isaligned with cavity 442 when shim 700 is aligned with first spacer 400.In some embodiments, the dovetail extension 712 is omitted. Althoughembodiments are discussed herein including a dovetail extension 712, itwill be appreciated that the shim 700 can be coupled to the first spacerusing any suitable coupling elements, such as a non-dovetail projection,a fixation device, a magnetic coupling, one or more rails, a ball-detentcoupling, a spring-clip coupling, and/or any other suitable connection.

In some embodiments, a recess 716 is defined in lower surface 706 ofshim 700. Recess 716 is sized and configured to receive protrusion 510of second spacer 500. Recess 716 couples shim 700 to second spacer 500.In some embodiments, protrusion 510 and recess 716 constrain one or moredegrees of freedom of joint 12 (such as medial/lateral position,proximal/distal position, flexion/extension orientation, etc.) whileallowing adjustment of one or more other degrees of freedom (such asinversion/eversion orientation, anterior/posterior position, etc.). Insome embodiments, recess 716 is similar and/or identical to recess 422formed in first spacer 400. Although embodiments are illustrated havinga shim 700 positioned between first spacer 400 and second spacer 500, itwill be appreciated that one or more shims 700 can be positioned betweenfirst spacer 400 and first bone 14 and/or second spacer 500 and secondbone 16, and are within in the scope of this disclosure. In someembodiments, the bone contact surfaces 406, 506 of first spacer 400and/or second spacer 500 include one or more features similar to thosediscussed above configured to couple the respective bone contact surface406, 506 to shim 700.

In some embodiments, recess 716 is a dovetail joint A cavity 718 isdefined in a lower surface 706 between rails 720. Cavity 718 is sizedand configured to receive a corresponding dovetail extension 712extending from a second shim 700. Although embodiments are discussedherein including a dovetail joint, it will be appreciated that the lowersurface 706 can define any suitable recess 716 sized and configured tocouple to an extension 712 defined by a second shim 700. In someembodiments, the recess 716 is omitted.

In some embodiments, recess 716 is positioned at a proximal edge oflower surface 706, although it will be appreciated that recess 716 canextend through any portion of lower surface 706 such that recess 716 isaligned with an extension 712 on a second shim 700 when multiple shimsare aligned. In some embodiments, recess 716 in lower surface 706 isvertically aligned with extension 712 extending from upper surface 704.

FIG. 13 illustrates a first spacer 400 having a first shim 700 a and asecond shim 700 b coupled thereto. First shim 700 a and second shim 700b are similar to shim 700 described above in conjunction with FIGS.16-17, and similar description is not repeated herein. First shim 700 ais coupled to first spacer 400. Dovetail extension 712 a extending fromupper surface 704 a of shim 700 a is inserted into cavity 442 formed infirst spacer 400 a. Dovetail extension 712 a and channel 442 maintainfirst shim 700 a in a fixed position with respect to first spacer 400 a.Second shim 700 b is coupled to first shim 700 a. Dovetail extension 712b extending from upper surface 704 b of second shim 700 b is insertedinto channel 716 a defined by first shim 700 a. Dovetail extension 712 band cavity 716 a maintain the second shim 700 b in a fixed position withrespect to first shim 700 a and first spacer 400. Although embodimentsare illustrated with two shims 700 a, 700 b, it will be appreciated thatany number of shims can be inserted between a first spacer 400 and asecond spacer 500.

In some embodiments, each of shims 700 a, 700 b has a predeterminedthickness. For example, in various embodiments, each of shims 700 a, 700b can have a predetermined thickness of about 1 mm to about 5 mm, suchas, for example, 1 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 5 mm, and/orany other suitable thickness. It will be appreciated that shims 700 a,700 b can have a greater and/or less thickness in some embodiments. Insome embodiments, each of shims 700 a, 700 b has a different thickness.For example, in some embodiments, first shim 700 a has a first thicknessand second shim 700 b has a second thickness that is less than, equalto, or greater than the first thickness. A surgeon can select anysuitable combination of shims 700 a, 700 b having similar and/ordifferent thicknesses to correct laxity in joint 12.

FIGS. 18-26 illustrate resection guide 600, in accordance with someembodiments. Resection guide 600 is configured to be coupled to thefirst spacer 400 and/or the second spacer 500. Resection guide 600includes a guide adapter 602, an adjustable guide body 604, and anadjustment knob 606. As best shown in FIG. 20, guide adapter 602includes a body 610 having a flat coupling element 612 and a couplingextension 620 extending from body 610. Flat coupling element 612includes a substantially flat body 614 sized and configured forinsertion into slot 430 formed in first spacer 400. Flat body 614includes one or more coupling elements 616 configured to maintain guideadapter 602 in a fixed position within slot 430. For example, in someembodiments, coupling elements 616 include leaf-spring elements 618configured to apply a force to an inner surface of slot 430 to maintainguide adapter 602 in a fixed position with respect to first spacer 400,although it will be appreciated that any suitable coupling element canbe used to maintain flat body 614 in the slot 430.

As best shown in FIGS. 22-24, adjustable guide 604 includes a guide body626 having a first leg 624 a and a second leg 624 b extending from asuperior edge of the guide body 626. First leg 624 a and second leg 624b are spaced apart to define an adjustment slot 622. Adjustment slot 622is sized and configured to receive a coupling element 620 extending fromguide adapter 602. Coupling element 620 is slideable within slot 622 toadjust the vertical position of adjustable guide 604 with respect tofirst spacer 400. As best shown in FIG. 23, in some embodiments, firstleg 624 a and/or second leg 624 b includes one or more indicators 630corresponding to a resection depth of a cut to be formed in second bone16. The resection depth can correspond to a thickness of an implant tobe coupled to second bone 16 after forming a resection cut in secondbone 16. In some embodiments, coupling element 620 includes one or morethreads configured to threadably couple to a locking element 606.Although embodiments are illustrated including a first leg 624 a and asecond leg 624 b, it will be appreciated that one of the legs 624 a, 624b can be omitted.

In some embodiments, guide body 626 defines a resection slot 660extending through body 626 from a proximal surface 636 a to a distalsurface 636 b. Resection slot 660 extends longitudinally from a firstend 662 a to a second end 662 b. The longitudinal profile of resectionslot 660 corresponds to a cut profile of a resection to be formed in oneor more bones of joint 12, such as second bone 16. Resection slot 660 issized and configured to receive a cutting tool (e.g., a reciprocatingsaw or blade) therein. The cutting tool inserted into the resection slot660 and manipulated to form a resection and/or revision in first bone 14and/or second bone 16 after positioning adjustable guide 604 in aselected position.

In some embodiments, guide body 626 defines a plurality of first guideholes 632 a-632 d and a plurality of second guide holes 634 a-634 bextending therethrough. The guide holes 632 a-632 d, 634 a-634 b areeach sized and configured to receive a fixation device therethrough.Each fixation device can include any suitable fixation device, such as ak-wire, a screw, and/or a pin, to list only a few possibilities. In someembodiments, the plurality of first fastener holes 632 a-632 d and theplurality of second fastener holes 634 a-634 b are sized and configuredto receive similar temporary fixation devices, although it will beappreciated that the plurality of first fastener holes 632 a-632 dand/or the plurality of second fastener holes 634 a-634 b can be sizedand configured to receive different temporary fixation devices.

In some embodiments, each of the plurality of first fastener holes 632a-632 d extend from a proximal surface 636 a of guide body 626 to adistal surface 636 b. First guide holes 632 a-632 d each extend throughguide body 626 along substantially parallel axes. In some embodiments,each of the first guide holes 632 a-632 d extend through guide body 626at a first angle with respect to a horizontal axis of guide body 626. Inthe illustrated embodiment, each of the first guide holes 632 a-632 dhave a hole axis parallel with the horizontal axis of guide body 626,although it will be appreciated that the first guide holes 632 a-632 dcan extend through guide body 626 along a hole axis positioned at anangle with respect to the horizontal axis of guide body 626.

In some embodiments, each of the plurality of second guide holes 634a-634 b extend from proximal surface 636 a of guide body 626 to distalsurface 636 b. In some embodiments, each of the second guide holes 634a-634 b extend through the guide body 626 at a second angle with respectto the horizontal axis of the guide body 626, different than the firstangle. In the illustrated embodiment, each of the second guide holes 634a-634 b extend through the guide body 626 along an axis at a secondangle between 0 and 90° with respect to the horizontal axis, although itwill be appreciated that the second guide holes 634 a-634 b can extendthrough the guide body 626 at any suitable angle.

As best shown in FIGS. 25-26, in some embodiments, locking element 606is a locking knob 640 including a body 642 defining a channel 644extending therethrough. Channel 644 includes one or more mating features646 configured to couple locking knob 640 to coupling element 620. Forexample, in embodiments including a thread 626 formed on couplingelement 620, mating feature 646 includes a complementary internal thread658. The locking knob 640 can be threadably engaged with threads 626 ofcoupling element 620 to advance locking knob 640 onto coupling element620.

In some embodiments, locking knob 640 includes a tool engagement feature648. Tool engagement feature 648 is sized and configured to engage witha tool, such as a wrench, to apply a tightening and/or loosening forceto locking knob 640. In some embodiments, tool engagement feature 648includes a coupling surface 650 having a hexagonal cross-sectionalsurface/plane with each side of the coupling surface 650 defining a flator planar face 670 configured to provide an interference fit betweenlocking knob 640 and the corresponding hexagonal wrench. Althoughembodiments are discussed herein including a hexagonal coupling surface,it will be appreciated that any suitable tool engagement feature 648 canbe used to couple locking knob 640 to a tool.

In some embodiments, locking knob 640 includes one or more scallopedgripping surfaces 652 a-652 b. Scalloped gripping surface 652 a-652 binclude a plurality of raised surfaces 654 separated by a plurality ofchannels 656. The plurality of raised surfaces 654 and/or the pluralityof channels 656 provide a textured gripping surface for a user to gripand manipulate locking knob 640. For example, in some embodiments,scalloped gripping surfaces 652-652 b allow a user to hand tightenand/or loosen locking knob 640 onto coupling element 620 prior to and/orafter engagement of a tool with tool engagement feature 648. Althoughembodiments are illustrated with two gripping surfaces 652 a-652 b, itwill be appreciated that locking knob 640 can include a lesser and/orgreater number of gripping surfaces.

In some embodiments, locking knob 640 is configured to be rotatablycoupled to coupling element 620. Locking knob 640 can engaged withthreads 626 of coupling element 620 to apply a locking force toadjustable guide 604 to maintain adjustable guide 604 in a fixedposition. Locking knob 640 can be loosened and/or partially disengagedfrom threads 626 to allow vertical adjustment of adjustable guide 604with respect to guide adapter 602. For example, in some embodiments,coupling element 620 is sized and configured to slide within slot 622defined by adjustable guide 604. Locking knob 640 can include one ormore spiral channels 668 extending about body 642. The spiral channels668 enable body 642 to be compressed when locking knob 606 is tightenedagainst adjustable guide 604 to increase the force applied to adjustableguide 604. In the illustrated embodiment, spiral channels 668 allow adistal portion 670 of the locking knob 640 to act as a leaf-spring toincrease the force applied to the adjustable guide 604.

Although embodiments are discussed herein including a locking knob 640,it will be appreciated that locking element 606 can include any suitablecoupling mechanism. For example, in various embodiments, locking element606 can include one or more of a knob, a lever, a toggle, a ball-detent,and/or any other suitable coupling mechanism.

The spacer assembly 300 and the adjustable guide assembly 600 can beconfigured for use in a revision surgery. Prior to a revision surgery, aCT or MRI scanned image or series of images is taken of a patient'sankle 12 and then converted from, e.g., a DICOM image format, to a solidcomputer model of the ankle including the calcaneus, talus, tibia,navicular, and fibula to determine implant alignment, type, and sizingusing specialized modeling methods that are often embodied in computersoftware. The computer model illustrates deformities and/or laxity inthe joint 12 that was not corrected by and/or occurred subsequent to aprevious primary replacement surgery. The computer model can furtherillustrate foreign objects coupled to the joint 12, such as implantsinstalled during the primary replacement surgery.

After generating the computer model, a first spacer 400, 400 a and asecond spacer 500, 500 a are generated to match the solid computermodel. The spacers 400, 500 can be generated using any suitable method,such as, for example, using a rapid prototyping technique including aprocessing unit and a rapid prototyping machine, as discussed in greaterdetail in U.S. Pat. No. 5,768,134, issued on Jun. 16, 1998, entitled“Method for Making a Perfected Medical Model on the Basis of DigitalImage Information of a Part of the Body,” which is incorporated hereinby reference in its entirety. After generating the spacers 400, 500, thejoint 12 of the patient can be surgically accessed and one or more ofthe preexisting primary implants can be removed from the joint 12. Insome embodiments, a conversion instrument 200 can be used to form one ormore additional revision cuts in one of first bone 14 or second bone 16.

After resection of first bone 14 and/or second bone 16 and/or removal ofone or more implants from joint 12, the first spacer 400, 400 a and thesecond spacer 500, 500 a are positioned within the joint space toposition the first and second bones 14, 16 in a pre-operatively plannedcorrected position. The first spacer 400, 400 a is positioned within theresection formed in the first bone 14. The first spacer 400, 400 a canbe manipulated until one or more of the bone contact surfaces 404, 414 asecurely engage with the topography of the first bone 14. As shown inFIG. 27, with the first spacer 400 a engaged with the first bone, one ormore temporary fixation devices 350 a, such as k-wires, are insertedthrough one or more of the fixation holes 416 a-416 b, 428 a-428 b totemporarily anchor the first spacer 400 a to the first bone 14. Thesecond spacer 500, 500 a is positioned in contact with the second bone16. For example, the second spacer 500, 500 a can be manipulated until abone contact surface 504 securely engages with the topography of thesecond bone 16. With the second spacer 500, 500 a securely engaged withthe second bone 16, one or more temporary fixation devices 350 b, suchas k-wires, are inserted through one or more of the fixation holes 514a-514 b to temporarily anchor the second spacer 500, 500 a to the secondbone 16.

With further reference to FIG. 27, a coupling surface 406 of firstspacer 400 a is positioned in an abutting relationship with a couplingsurface 506 of second spacer 500 a. Mating element 512 extending fromcoupling surface 506 of second spacer 500 a is inserted into recess 422formed in coupling surface 406. First spacer 400 a and second spacer 500a position first bone 14 and second bone 16 in a predetermined positionwith respect to one or more of a varus/valgus orientation, aflexion/extension orientation, an inversion/eversion orientation, ananterior/posterior position, a medial/lateral position, and/or aproximal/distal position. In some embodiments, mating element 512 andrecess 422 constrain one or more degrees of freedom of joint 12 (such asmedial/lateral position, proximal/distal position, flexion/extensionorientation, etc.) while allowing adjustment of one or more otherdegrees of freedom (such as inversion/eversion orientation,anterior/posterior position, etc.). In some embodiments, the first guide400 a and/or the second guide 500 a include one or more featuresconfigured to verify an alignment and/or position of the respectiveguide 400 a, 500 a, such as through fluoroscopy.

After positioning the first spacer 400 a and/or the second spacer 500 ain the joint space 12, one or more shims 700 a, 700 b can be coupled tothe first spacer 400 a and/or the second spacer 500 a to correct laxityin the joint 12. For example, in the illustrated embodiment, a firstshim 700 a is coupled to a coupling surface 406 of the first spacer 400a and a second shim 700 b is coupled to the first shim 700 a. The secondshim 700 b abuts and couples to the coupling surface 506 of secondspacer 500 a. The number and/or thickness of shims 700 a, 700 b can beselected intraoperatively to correct pre-existing laxity and/orintraoperatively generated laxity in joint 12.

The surgeon then couples adjustable guide 600 to one of the first spacer400 and/or second spacer 500. In the illustrated embodiments, theadjustable guide 600 is coupled to first spacer 400. The couplingextension 620 of the guide adapter 602 is slideably engaged with theslot 430 formed in the first spacer 400. Leaf-spring elements 618 applya force to an inner surface of slot 430 to maintain the guide adapter602 in a fixed position with respect to first spacer 400. The adjustableguide 604 is coupled to the guide adapter 602 by inserting the couplingelement 620 of the guide adapter 602 into slot 622 defined by theadjustable guide 604. The locking knob 606 is threadably engaged withthe coupling element 620 to lock the adjustable guide 604 to the guideadapter 602.

The surgeon adjusts the vertical position of adjustable guide 604 byloosening locking knob 606 and sliding adjustable guide 604 up/down toadjust a corresponding resection depth of a cut to be formed in thesecond bone 16. The position of adjustable guide 604 can be viewed usingfluoroscopy. A k-wire, saw blade, and/or other element can be insertedat the desired resection location to visualize the resection and todetermine the appropriate resection depth intraoperatively.

In some embodiments, markings on adjustable guide 604 indicate thedistance of the resection cut in second bone 16 from a resection cut infirst bone 14. The first leg 624 a and/or the second leg 624 b ofadjustable guide 604 include one or more depth markings to provide avisual indication to the surgeon regarding the depth of the resectioncut. The depth of the resection can be further influenced by thethickness of an implant to be coupled to second bone 16. After selectinga desired resection cut depth, locking element 606 is tightened to fixthe position of adjustable guide 604. As shown in FIGS. 27-28, one ormore guide elements 352 a-352 b, such as guide pins, are insertedthrough one or more of the first guide holes 632 a-632 d and/or secondguide holes 634 a-634 b formed through guide body 626.

After inserting the guide pins, the spacer assembly 300 and all fixationelements, except the guide element 352 a-352 b, are removed from thejoint 12. The guide body 626 is re-positioned with respect to the secondbone 16 by sliding the guide elements 352 a-352 b through first guideholes 632 a-632 d and/or second guide holes 634 a-634 b, as shown inFIG. 28. A resection cut is formed in second bone 16 by inserting acutting instrument through resection slot 660 defined by the guide body.In some embodiments, a separate resection cut guide can be coupled tosecond bone 16 by engaging the resection cut guide with the temporaryguide elements in second bone 16. Removal of spacer assembly 300prevents a resecting cut from intersecting the spacers and furtherallows the resection guide body 626 to be positioned closer to thesecond bone 16. Additional fixation elements, such as k-wires or guidepins, may be inserted through one or more of fixation holes 634 a-634 bto further fix the position of guide body 626 with respect to the secondbone 16.

If adjustment of the resection depth is necessary, the guide body 626can be adjusted by repositioning the guide pins into an alternative setof guide holes 632 a-632 d. For example, in some embodiments, a firstset of guide holes 632 a, 632 b is positioned above a second set ofguide holes 632 c, 632 d. The first and second sets of guide holes 632a-632 d allow adjustment of the resection depth by a predeterminedamount, for example, a predetermined amount in the range of +/−0-5 mm,such as 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm,and/or 5 mm. It will be appreciated that guide holes 632 a-632 d canhave a greater and/or lesser spacing allowing any predetermined amountof adjustment.

After fixing the position of guide body 626, second bone 16 is resected.Guide body 626, guide elements 352 a-352 b, and/or other elements areremoved from second bone 16. The resected space between first bone 14and second bone 16 is cleared of all resected bone down to the level ofthe resection cut, such as a flat cut in second bone 16.

FIGS. 29-30 illustrate an alternative embodiment of a spacer assembly300 b including a first spacer 400 b configured to be coupled to animplant 480 installed in first bone 14, in accordance with someembodiments. The spacer assembly 300 b is similar to the spacer assembly300 discussed above in conjunction with FIGS. 6-9, and similardescription is not repeated herein. The spacer assembly 300 a includes afirst spacer 400 b and a second spacer 500 b configured to position thefirst bone 14 and the second bone 16 in a corrected alignment. In someembodiments, the corrected alignment of joint 12 corresponds to apreoperatively planned deformity correction that is planned based onanatomic references and/or surgeon preferences. First spacer 400 band/or second spacer 500 b set one or more degrees of freedom of joint12. For example, in various embodiments, the spacer assembly 300 b cancorrect one or more of a varus/valgus orientation, a flexion/extensionorientation, an inversion/eversion orientation, an anterior/posteriorposition, a medial/lateral position, and/or a proximal/distal positionbetween the first bone 14 and the second bone 16 intraoperatively.

First spacer 400 b includes a body 402 a extending between upper surface404 a and a lower surface 406 a. The upper surface 404 a defines aplanar surface. An implant coupling element 482 extends from the uppersurface 404 a. The implant coupling element 482 is sized and configuredto be received within a lock detail 484 defined by an implant 480coupled to the first bone 14. The implant 480 can include any suitableimplant, such an articulation implant coupled to the first bone 14during a previous joint replacement surgery and/or implantedconcurrently with a current ankle replacement/revision surgery.

FIGS. 31-33 illustrate an alternative embodiment of a spacer assembly300 c including a monolithic spacer 800, in accordance with someembodiments. The spacer assembly 300 c is similar to the spacer assembly300 discussed above, and similar description is not repeated herein. Thespacer assembly 300 c includes a monolithic spacer 800 configured toposition the first bone 14 and the second bone 16 in a correctedalignment. In some embodiments, the corrected alignment of joint 12corresponds to a preoperatively planned deformity correction that isplanned based on anatomic references and/or surgeon preferences.Monolithic spacer 800 sets one or more degrees of freedom of joint 12.For example, in various embodiments, the monolithic spacer 800 cancorrect one or more of a varus/valgus orientation, a flexion/extensionorientation, an inversion/eversion orientation, an anterior/posteriorposition, a medial/lateral position, and/or a proximal/distal positionbetween the first bone 14 and the second bone 16 intraoperatively.

As best shown in FIGS. 32-33, monolithic spacer 800 includes a body 802having a thickness extending between a first bone contacting surface 804and a second bone contacting surface 806. Body 802 further extendslongitudinally between a proximal surface 808 a and a distal surface 808b and has a width extending between a first side surface 810 a and asecond side surface 810 b. First bone contacting surface 804 isconfigured to abut a surface of first bone 14 and second bone contactingsurface 806 is configured to abut a surface of the second bone 16, suchas a superior portion of a talus. In some embodiments, bone contactsurfaces 804, 806 are configured to engage a previously resected bonesurface of respective first bone 14 or second bone 16 and/or definepatient-specific profiles configured to surface match respective firstbone 14 and/or second bone 16. For example, first bone contactingsurface 804 can be configured to engage a previously resected surface offirst bone 14 and second bone contacting surface 806 can be configuredto interface with existing bony anatomy and/or cartilage or other softtissue of second bone 16.

In some embodiments, monolithic spacer 800 includes a bone engagingstructure 812 coupled to a proximal surface 808 a of body 802. Boneengaging structure 812 extends superiorly from the proximal surface 808a terminating above first bone contacting surface 804. Bone engagingstructure 812 extends between a bone contacting surface 814 a and anopposing surface 814 b, an upper surface 816 a and a lower surface 816b, and first and second side surfaces 818 a, 818 b. In some embodiments,the bone contacting surface 814 a includes a patient-specific profileconfigured to surface-match a portion of first bone 14, such as ananterior surface of a tibia, for example. Bone engaging structure 812 isconfigured to maintain monolithic spacer 800 in a fixedanterior/posterior position with respect to first bone 14. Bone engagingstructure 812 defines a slot 830 extending from opposing surface 814 bat least partially into bone engaging structure 812. In someembodiments, slot 830 extends from opposing surface 814 b to bonecontacting surface 814 a. Slot 830 is sized and configured to receive aflat body 614 of resection guide 600 therein.

In some embodiments, monolithic spacer 800 includes a plurality of firstfixation holes 820 a-820 d extending from opposing surface 814 b to bonecontacting surface 814 a. The one or more fixation holes 820 a-820 d aresized and configured to receive a fixation element therethrough. Thefixation elements can include any suitable fixation element, such as ak-wire, screw, pin, and/or any other suitable fixation element. Thefixation elements are configured to maintain monolithic spacer 800 in afixed position with respect to first bone 14 and/or second bone 16. Insome embodiments, the fixation holes 820 a-820 d are parallel, althoughit will be appreciated that two or more of fixation holes 820 a-820 dcan have non-parallel axes.

In some embodiments, monolithic spacer 800 includes a plurality ofsecond fixation holes 822 a-822 b extending from one of a first sidewall 810 a or a second side wall 810 b of body 802 to the other of thefirst side wall 810 a or the second side wall 810 b. The fixation holes822 a-822 b are angled with respect to first and second side surfaces810 a, 810 b such a first side of each of the fixation holes 822 a-822 bis positioned proximally of a second side. In some embodiments, fixationholes 822 a-822 b extend through body 802 along intersecting hole axis,although it will be appreciated that the fixation holes 822 a-822 b canextend through the body 802 along non-intersecting hole axis in someembodiments.

In some embodiments, a kit can include multiple monolithic spacers eachhaving a different thickness. For example, in some embodiments, a kitcan include a first monolithic spacer having a first thickness between afirst bone contact surface 804 and a second bone contact surface 806 anda second monolithic spacer having a second thickness between a firstbone contact surface 804 and a second bone contact surface 806. Thesecond thickness can be greater than the first thickness. A surgeon canselect one of the first monolithic spacer or the second monolithicspacer based on laxity between first bone 14 and second bone 16.Although embodiments are discussed using two monolithic spacers, it willbe appreciated that any number of monolithic spacers having any numberof thicknesses can be included, and are within the scope of thisdisclosure.

FIG. 34 illustrates a patient-specific spacer assembly 300 d including amonolithic spacer 800 a having a cutting guide 850 coupled thereto, inaccordance with some embodiments. The cutting guide 850 is similar tothe guide 250 discussed above in conjunction with FIG. 3, and similardescription is not repeated herein. In some embodiments, the cuttingguide 850 is configured to guide a cutting instrument for forming one ormore cuts in first bone 14 and/or second bone 16. Cutting guide 850 candefine a slot 860 sized and configured to receive a coupling extension620 of an adjustable guide 600 therein.

FIGS. 35-38 illustrates a spacer assembly 300 e including a first spacer400 c and a second spacer 500 c having a telescoping connectiontherebetween, in accordance with some embodiments. The spacer assembly300 e is similar to the spacer assembly 300 discussed above, and similardescription is not repeated herein.

In some embodiments, first spacer 400 c and second spacer 500 c areconfigured to engage one another via a telescoping connection. Forexample, first spacer 400 c includes a body 402 c defining a channel 470extending from lower surface 406 c into body 402 c as best seen in FIG.37. Channel 470 can be a closed and/or open channel having any suitableshape, such as a closed geometric shape (e.g., cylindrical, square,etc.), an open shape, and/or any other suitable shape. For example, inthe illustrated embodiment, channel 470 defines a closed square shapeextending about the periphery of lower surface 406 a, although it willbe appreciated that channel 470 can have any suitable shape.

In some embodiments, a plurality of height adjustment holes 472 a-472 dextend through body 402 a from a proximal surface 408 a into channel470. The height adjustment holes 472 a-472 d are sized and configured toreceive a fixation device therein, such as, for example, a k-wire, apin, a screw, and/or any other suitable fixation device. Althoughembodiments are illustrated having four sets of height adjustment holes472 a-472 d, it will be appreciated that body 402 a can define anynumber of height adjustment holes 472 a-472 d extending from any of thesurfaces of body 402 a into channel 470.

In some embodiments, second spacer 500 c includes an adjustment body 570extending from upper surface 506 c. Adjustment body 570 extends apredetermined height above upper surface 506 c. Adjustment body 570includes a perimeter wall 572 defining a hollow interior 574. Adjustmentbody 570 is sized and configured for insertion into channel 470 formedin first spacer 400 a. For example, in some embodiments, perimeter wall572 defines a closed shape corresponding to the closed shape of channel470. In other embodiments, perimeter wall 572 defines an open shapecorresponding to a portion of channel 470. Perimeter wall 572 can extenda predetermined height above the upper surface 506 a that is less than,equal to, or greater than a depth of channel 470.

In some embodiments, perimeter wall 572 defines a plurality of heightadjustment holes 574 a-574 c extending from a proximal surface 578 tohollow interior 574. The height adjustment holes 574 a-574 c areconfigured to receive a fixation device therein, such as a k-wire, apin, a screw, and/or any other suitable fixation device. In someembodiments, height adjustment holes 574 a-574 c have a spacing similarand/or identical to the spacing of height adjustment holes 472 a-472 dformed in first spacer 400 c, although it will be appreciated thatheight adjustment holes 574 a-574 c can have a greater and/or lesserspacing than height adjustment holes 472 a-472 d.

In use, adjustment body 570 is configured to be inserted into channel470 to couple first spacer 400 c to second spacer 500 c. First spacer400 c and second spacer 500 c define a minimum spacing when adjustmentbody 570 is fully inserted into channel 470. For example, in someembodiments, adjustment body 570 is inserted into channel 470 until anupper surface of the perimeter wall 572 contacts an inner surface 476 ofchannel 470, although it will be appreciated that the adjustment body570 and/or the channel 470 can be tapered such that the upper surface ofthe perimeter wall 572 does not contact the inner surface 476 of thechannel 470 when fully inserted. If laxity is observed in joint 12, thedistance between first spacer 400 c and second spacer 500 c can beincreased.

In some embodiments, a distance between first spacer 400 c and secondspacer 500 c can be adjusted by sliding a portion of adjustment body 570out of channel 470 to increase the distance between first spacer 400 cand second spacer 500 c. Adjustment body 570 can be adjusted from aminimum spacing (in which the adjustment body 570 has a maximum portionlocated within the cavity 470) to a maximum spacing (in which theadjustment body 570 has a minimum portion located within the cavity470). In various embodiments, the spacing can be adjusted continuouslyand/or discretely from the minimum spacing to the maximum spacing.

In some embodiments, a selected spacing of first spacer 400 c and secondspacer 500 c is maintained by one or more fixation devices. First spacer400 c defines a first plurality of height adjustment holes 472 a-472 dand second spacer 500 c defines a second plurality of height adjustmentholes 574 a-574 c. The position of each of height adjustment holes 472a-472 d, 574 a-574 c is selected such that at least one set of the firstplurality of adjustment holes 472 a-472 d is aligned with at least oneset of the second plurality of adjustment holes 574 a-574 c when firstspacer 400 c and second spacer 500 c are positioned at one or morepredetermined distances. A fixation element (not shown), such as a pin,can be inserted through one of the first plurality of adjustment holes472 a-472 d and at least partially into a corresponding (i.e., aligned)one of the second plurality of adjustment holes 574 a-574 c to maintainfirst spacer 400 c and second spacer 500 c in a selected spacing. Insome embodiments, a fixation element is inserted through each adjustmenthole in a pair of aligned adjustment holes 472 a-472 d, 574 a-574 c.

FIG. 39 illustrates a spacer assembly 300 f including a first spacer 400d and one or more shims 700 c, 700 d, in accordance with someembodiments. First spacer 400 d is similar to first spacer 400 discussedabove and shims 700 c, 700 d are similar to shim 700 described above,and similar description is not repeated herein. In some embodiments,coupling surface 406 d of the first spacer 400 d and/or a lower surface706 of the shims 700 c, 700 d are configured to directly contact asurface of second bone 16. In some embodiments, coupling surface 406 dand/or the lower surface 706 of each of the shims 700 c, 700 d defines aplanar surface configured to interact with a partially and/or fullyresected surface of the second bone 16. In other embodiments, thecoupling surface 406 d and/or the lower surface 706 of the shims 700 c,700 d includes a patient-specific surface configured to match a surfacetopography of at least a portion of the second bone 16.

In some embodiments, the first spacer 400 d and one or more shims 700 c,700 d are configured to fill a joint space between the first bone 14 andthe second bone 16 and position the bones 14, 16 in a correctedalignment. In some embodiments, the corrected alignment of the joint 12corresponds to a preoperatively planned deformity correction that isplanned based on anatomic references and/or surgeon preferences. Thespacer 400 d and the one or more shims 700 c, 700 d set a varus/valgusand/or flexion/extension relationship between the first bone 14 and thesecond bone 16 intraoperatively.

FIGS. 40-41 illustrates a spacer assembly 300 g including a first spacer400 e and an angled shim 700 e, in accordance with some embodiments. Thespacer assembly 300 g is similar to the spacer assembly 300 f discussedabove in conjunction with FIG. 39, and similar description is notrepeated herein. The spacer assembly 300 g includes an angled shim 700 ehaving a body 702 e including one or more angled facets 758 a, 758 b.The body 702 e includes a planar upper surface 704 e and a lower surface706 e including a plurality of facets 758 a, 758 b each extending at anangle with respect to the upper surface 704 e. For example, in someembodiments, the lower surface 706 e includes a first facet 758 aextending at a first angle with respect to the upper surface 704 and asecond facet 758 b extending at a second angle with respect to the uppersurface 704. The first facet 758 a and the second facet 758 b areperpendicular, although it will be appreciated that the first facet 758a can be positioned at any angle with respect to the second facet 758 b.In some embodiments, the lower surface 706 e includes a patient-specificprofile configured to match a surface profile of the second bone 16.

In some embodiments, the body 702 e of the shim 700 e is configured toabut a second bone 16. The shim 700 e and the first spacer 400 e areconfigured to fill a joint space between first bone 14 and second bone16 and position bones 14, 16 in a corrected alignment. In someembodiments, the corrected alignment of joint 12 corresponds to apreoperatively planned deformity correction that is planned based onanatomic references and/or surgeon preferences. First spacer 400 e andshim 700 e set one or more degrees of freedom of joint 12. For example,in various embodiments, the spacer assembly 300 e can correct one ormore of a varus/valgus orientation, a flexion/extension orientation, aninversion/eversion orientation, an anterior/posterior position, amedial/lateral position, and/or a proximal/distal position between thefirst bone 14 and the second bone 16 intraoperatively.

FIGS. 42-43 illustrate a drill guide mount 900 configured to be insertedinto a resected joint 12, in accordance with some embodiments. The drillguide mount 900 is sized and configured to receive a drill guidecartridge 902. The drill guide mount 900 may be manufactured from aresilient polymer material of the type that is suitable for use inconnection with stereo lithography, selected laser sintering, or thelike manufacturing equipment, e.g., a polyamide powder repaid prototypematerial is suitable for use in connection with the selective lasersintering.

Drill guide mount 900 has a somewhat rectangular body 904 having a frontside 906, a rear side 908, top side 910, bottom side 912, and a pair ofopposed sides 914 and 916. Front side 906 defines a recess 918 sized andconfigured to slideably receive tibial drill guide 902 therein. Recess918 communicates with a recess 920 defined by bottom side 912 and arecess 922 defined by top side 910 such that body 904 is substantiallyhollow. Tibial drill guide cartridge 902 has a substantially rectangularelongate body 954 that may be formed from a more substantial materialthan tibial drill guide mount 900 such as, for example, metals,ceramics, or the like. The geometry of the sides of tibial drill guidecartridge 902 are respectively complementary to the sides 914, 916 oftibial drill guide mount 700.

A mounting plate 950, as best seen in FIG. 43, has a substantiallyrectangular body 952 that is fabricated from a material including, butnot limited to, metals, ceramics, or other suitably rigid and durablematerial. Body 952 defines an aperture 954 the extends from a front sideto a back side and has a similar geometry of recess 918 of drill guidemount 900 such that drill guide cartridge 902 may be received therein.Body 952 also defines a pair of through holes 960 that are arranged onbody 952 such that they correspond to holes 938 of tibial drill guidemount 700 and are sized and configured to receive a k-wire or pintherein. Additional description of a tibial drill guide mount can befound in U.S. Pat. No. 8,808,303, which is incorporated by referenceherein in its entirety.

Referring again to FIG. 42, bottom side 912 of drill guide mount 900includes a dovetail joint 970. Dovetail joint 970 has a similarconstruction to the dovetail joint 440 described above with respect tothe first spacer 400. A cavity 972 is defined in bottom side 912 betweenrails 974. Cavity 972 is sized and configured to receive a correspondingdovetail extension 712 extending from a shim 700. Although embodimentsare discussed herein including a dovetail joint 970, it will beappreciated that bottom side 912 can define any suitable cavity sizedand configured to couple to extension 712 defined by the shim 700.

Shim 700 is configured to provide stability for the tibia drill guidemount 900 and the second bone 16. For example, one or more shims 700 canbe coupled to bottom side 912 fill a space between bottom side 912 and atop surface of resected second bone 16. In some embodiments, shims 700are identical to shims used to correct laxity between a first spacer 400and a second spacer 500. In other embodiments, one or more shims 700configured to couple to tibial drill guide mount 900 can have adifferent profile, different thickness, etc. from the shims positionedbetween first spacer 400 and second spacer 500.

In some embodiments, once one or more revision cuts are formed in joint12, for example using the spacer assembly 300 and adjustable guide 600discussed above, first bone 14 is prepared for a subsequent drillingoperation by inserting the drill guide mount 900 into the resected bonespace in first bone 14. The drill guide mount 900 and method of drill offirst bone 14 are similar to the use of a drill guide as described inU.S. Pat. Appl. Pub. 2015/0257899, which is incorporated by referenceherein in its entirety. The drill guide 900 is similar to the drillguide described in U.S. Pat. Appl. Pub. 2015/0257899, but includes adovetail joint 970 for receiving a portion of a shim 700 therein.

The disclosed system and method advantageously utilize custommanufactured surgical instruments, guides, and/or fixtures that arebased upon a patient's anatomy to reduce the use of fluoroscopy during asurgical procedure. In some instances, the use of fluoroscopy during asurgical procedure is eliminated altogether. The custom instruments,guides, and/or fixtures are created by imaging a patient's anatomy witha computer tomography scanner (“CT”), a magnetic resonance imagingmachine (“MRI”), or like medical imaging technology prior to surgery andutilizing these images to create patient-specific instruments, guides,and/or fixtures.

Although the invention has been described in terms of exemplaryembodiments, it is not limited thereto. Rather, the appended claimsshould be construed broadly, to include other variants and embodimentsof the invention, which may be made by those skilled in the art withoutdeparting from the scope and range of equivalents of the invention.

What is claimed is:
 1. A system, comprising: a monolithic spacer havinga body extending between a first surface and a second surface, whereinthe first surface is configured to abut a joint space of a first boneand the second surface includes a patient-specific topography matching asecond bone; and an adjustable guide comprising a guide adapterconfigured to be coupled the monolithic spacer and a guide body defininga resection slot, wherein the guide body comprises a first leg and asecond leg extending from the guide body and spaced apart to define aslot sized and configured to receive a coupling element extending fromthe guide adapter.
 2. The system of claim 1, wherein the monolithicspacer defines a first fixation hole extending from a first side to asecond side of the body at a first angle and a second fixation holeextending from the second side to the first side of the body at a secondangle.
 3. The system of claim 2, wherein the first fixation hole and thesecond fixation hole intersect within the body.
 4. The system of claim1, wherein the monolithic spacer comprises a bone engaging structureextending from the body in a first direction, wherein the bone engagingstructure extends between a bone contacting surface and an opposingsurface, and wherein the bone contacting surface is complementary to asurface topography of the first bone.
 5. The system of claim 4, whereinthe bone engaging structure defines at least one fixation hole extendingfrom the opposing surface to the bone contact surface.
 6. The system ofclaim 4, wherein bone engaging structure defines a slot sized andconfigured to receive a guide adapter of the adjustable guide slot.
 7. Asystem, comprising: a first spacer having a body with a first surfacethat is spaced-apart from a second surface, the second surface definesan adjustment channel and the first surface defines a patient-specificsurface profile to match a portion of the first bone; and a secondspacer suitably arranged so as to couple to a second bone, the secondspacer having a body with a first surface that is spaced-apart from asecond surface with an adjustment body projecting from the secondsurface, wherein the adjustment body is sized to be inserted into theadjustment channel in a telescoping arrangement, and further wherein thefirst spacer and the second spacer are configured to position the firstbone and the second bone in a predetermined alignment.
 8. The system ofclaim 7, wherein the body of the first spacer defines a first set ofadjustment holes extending from an outer surface to the adjustmentchannel and the adjustment body defines a second set of adjustment holesextending from an outer surface to an inner surface of the adjustmentbody, and wherein the first set of adjustment holes and the second setof adjustment holes are aligned when the adjustment body is insertedinto the adjustment channel.
 9. The system of claim 8, wherein the firstset of adjustment holes and the second set of adjustment holes define aplurality of discrete spacings between the first spacer and the secondspacer.
 10. The system of claim 8, wherein the first set of adjustmentholes and the second set of adjustment holes are arranged to receive afixation element therein.
 11. The system of claim 10, comprising anadjustable guide configured to be coupled to the first spacer.
 12. Thesystem of claim 10, wherein the first spacer defines a slot sized toreceive a portion of the adjustable guide.
 13. The system of claim 10,wherein the first spacer comprises a bone engaging structure projectingfrom the body in a first direction, wherein the bone engaging structureextends between a bone contacting surface and an opposing surface, andfurther wherein the bone contacting surface is complementary to asurface topography of the first bone.
 14. The system of claim 13,wherein the bone engaging structure defines at least one fixation holeextending from the opposing surface to the bone contact surface.
 15. Thesystem of claim 13, wherein bone engaging structure defines a slot sizedand configured to receive a guide adapter of the adjustable guide.